1. Field of the Invention
The present invention relates to a high power super capacitor, and more particularly, to a high power super capacitor that may increase a contact area without decreasing an area of an electrode active material layer and may decrease an equivalent series resistance by forming a conductive connection member using electric energy.
2. Description of the Related Art
A super capacitor uses an electrode assembly of a jellyroll type. The electrode assembly of the jellyroll type may be manufactured by inserting a separator between a first electrode plate and a second electrode plate that are formed by applying an electrode active material over a collector and drying the applied electrode active material, and then performing roll pressing and cutting, and by winding the first electrode plate and the second electrode plate with the inserted separator. Hereinafter, a conventional super capacitor employing the electrode assembly of the jellyroll type constructed as above will be described.
As shown in FIG. 1, the conventional super capacitor may includes an electrode assembly 1, a plurality of electrode tabs 2, and a plurality of second electrode tabs 3.
The electrode assembly 1 may include a separator 4, a first electrode plate 5, and a second electrode plate 6.
The separator 4 is disposed between the first electrode plate 5 and the second electrode plate 6 to thereby prevent the first electrode plate 5 and the second electrode plate 6 from being physically bonded with each other and thereby being electrically connected to each other.
The first and second electrode plates 5 and 6 include collectors 5a and 6a, and electrode active material layers 5b and 6b, respectively. The electrode active material layers 5b and 6b are respectively applied on both sides of the collectors 5a and 6a. Here, each of the electrode active material layers 5b and 6b includes conductive carbon, active carbon, and a binding agent. A contact area A where the electrode active material layer 5b is not applied is formed in the collector 5a. Although not illustrated in FIG. 1, the contact area A where the electrode active material layer 6b is not applied is formed in the collector 6a. As described above, the contact area A may be formed by removing the electrode active material layers 5b and 6b sprayed in an area where the contact area A is to be formed using a physical method employing a wiper and the like.
When the contact area A is formed in each of the collectors 5a and 6a, the first electrode tab 2 or the second electrode tab 3 may be bounded to each contact area A using a physical method such as pressing and the like. When the first electrode tab 2 or the second electrode tab 3 is pressed to the contact area A, the separator 4 is inserted between the first electrode plate 5 and the second electrode plate 6 and thereby is wound, whereby the electrode assembly 1 of the jellyroll type is formed as shown in FIG. 1. Next, the conventional super capacitor is manufactured by connecting an external lead terminal (not shown) to the first electrode tab 2 or the second electrode 3.
Like the conventional super capacitor, when the contact area A is formed in each of the collectors 5a and 6a, and the first electrode tab 2 or the second electrode tab 3 is bonded to the contact area A, a power loss and an exothermic characteristic may be deteriorated by increasing the number of first electrode tabs 2 and the number of second electrode tabs 3, and by distributing current applied to the collectors 5a and 6a. 
For example, when a single contact area A is formed in each of the collectors 5a and 6a and then the first electrode tab 2 or the second electrode tab 3 is bonded to the corresponding contact area A, the current may not be uniformly distributed whereby the power loss may increase. In addition, due to an equivalent series resistance, the exothermic characteristic (P=I2×R) may occur in a portion where the contact area A is bonded with the first electrode tab 2 or the second electrode tab 3. Here, I denotes the current and R denotes the equivalent series resistance. When n contact areas A are formed in each of the collectors 5a and 6a and then n first electrode tabs 2 or n second electrode tabs 3 are respectively bonded to the n contact areas A in order to enhance the above disadvantage, the current may be uniformly distributed through the first electrode tabs 2 or the second electrode tabs, whereby the power loss may be deteriorated. In addition, equivalent series resistances occurring in contact areas may be connected to each other in parallel, whereby the exothermic characteristic P may be reduced to I2×R/n. Here, n denotes the number of equivalent series resistances R.
As described above, in the conventional super capacitor, when significantly increasing the number of contact areas on a collector into consideration of the power loss or the exothermic characteristic, an area of a contact area may increase. Due to a decrease in an area of an electrode active material layer, a capacity deterioration may occur. When decreasing the number of contact areas, the conventional super capacitor may not be employed in a high power field due to an increase in the power loss or the exothermic characteristic.